The Battle of Kumanovo (Serbian: / Kumanovska bitka, Turkish: Kumanova Muharebesi), on 2324 October 1912, was a major battle of the First Balkan War. It was an important Serbian victory over the Ottoman army in the Kosovo Vilayet, shortly after the outbreak of the war. After this defeat, the Ottoman army abandoned the major part of the region, suffering heavy losses in manpower (mostly due to desertions) and in war materiel.

The First Balkan War (Serbian: Први балкански рат, Prvi Balkanski rat; Bulgarian: Балканска война; Greek: Αʹ Βαλκανικός πόλεμος; Turkish: Birinci Balkan Savaşı) lasted from October 1912 to May 1913 and involved actions of the Balkan League (the Kingdoms of Bulgaria, Serbia, Greece and Montenegro) against the Ottoman Empire. The Balkan states' combined armies overcame the initially numerically inferior (significantly superior by the end of the conflict) and strategically disadvantaged Ottoman armies and achieved rapid success.

The war was a comprehensive and unmitigated disaster for the Ottomans, who lost 83% of their European territories and 69% of their European population. As a result of the war, the League captured and partitioned almost all of the Ottoman Empire's remaining territories in Europe. Ensuing events also led to the creation of an independent Albania, which angered the Serbs. Bulgaria, meanwhile, was dissatisfied over the division of the spoils in Macedonia, and attacked its former allies, Serbia and Greece, on 16 June 1913 which provoked the start of the Second Balkan War.